OAI/NumberTheory/EgyptianFractions/SmoothRankin.lean

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15 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.Problem337.smooth_sum_le_euler_product line 12

    Source documentation

    A finite nonnegative sum over smooth numbers is bounded by the finite Euler product. Only the local prime-power series need to be summable.

    theorem smooth_sum_le_euler_product
        (f : ℕ → ℝ) (hf : ∀ n, 0 ≤ f n) (hf1 : f 1 = 1)
        (hmul : ∀ {m n}, Nat.Coprime m n → f (m * n) = f m * f n)
        (hsum : ∀ {p : ℕ}, p.Prime → Summable (fun j : ℕ => ‖f (p ^ j)‖))
        (N : ℕ) (s : Finset ℕ) (hs : ∀ n ∈ s, n ∈ N.smoothNumbers) :
        (∑ n ∈ s, f n) ≤ ∏ p ∈ N.primesBelow, ∑' j : ℕ, f (p ^ j) := by
    …
  2. theorem OAI.Problem337.rankin_weight_bound line 29

    Source documentation

    The elementary exponential weight used in Rankin's tail estimate.

    theorem rankin_weight_bound {V β : ℝ} {n : ℕ}
        (hβ : 0 ≤ β) (hn : Real.exp V ≤ (n : ℝ)) :
        1 ≤ Real.exp (-β * V) * (n : ℝ) ^ β := by
    …
  3. theorem OAI.Problem337.smooth_rankin_bound line 43

    Source documentation

    Rankin's trick followed by a finite Euler product. This form applies to f n = τ(n)^r / n; the local weight then has exponent -1 + β.

    theorem smooth_rankin_bound
        (f : ℕ → ℝ) (hf : ∀ n, 0 ≤ f n) (hf1 : f 1 = 1)
        (hmul : ∀ {m n}, Nat.Coprime m n → f (m * n) = f m * f n)
        {V β : ℝ} (hβ : 0 ≤ β)
        (hsum : ∀ {p : ℕ}, p.Prime →
          Summable (fun j : ℕ => ‖f (p ^ j) * ((p ^ j : ℕ) : ℝ) ^ β‖))
        (N : ℕ) (s : Finset ℕ) (hs : ∀ n ∈ s, n ∈ N.smoothNumbers)
        (hlarge : ∀ n ∈ s, Real.exp V ≤ (n : ℝ)) :
        (∑ n ∈ s, f n) ≤ Real.exp (-β * V) *
          (∏ p ∈ N.primesBelow, ∑' j : ℕ, f (p ^ j) * ((p ^ j : ℕ) : ℝ) ^ β) := by
    …
  4. def OAI.Problem337.divisorHarmonicWeight line 77

    Source documentation

    The multiplicative weight occurring in divisor harmonic moments.

    def divisorHarmonicWeight (r n : ℕ) : ℝ :=
    …
  5. theorem OAI.Problem337.divisorHarmonicWeight_nonneg line 80
  6. theorem OAI.Problem337.divisorHarmonicWeight_one line 84
  7. theorem OAI.Problem337.divisorHarmonicWeight_mul line 87
  8. theorem OAI.Problem337.divisorHarmonicWeight_prime_power line 92
  9. theorem OAI.Problem337.summable_successor_pow_geometric line 103
  10. theorem OAI.Problem337.divisorHarmonicWeight_local_summable line 116
  11. theorem OAI.Problem337.divisor_smooth_rankin_bound line 125

    Source documentation

    Concrete smooth-prefix Rankin estimate for any natural moment order.

    theorem divisor_smooth_rankin_bound (r : ℕ) {V β : ℝ} (hβ : 0 ≤ β) (hβone : β < 1)
        (N : ℕ) (s : Finset ℕ) (hs : ∀ n ∈ s, n ∈ N.smoothNumbers)
        (hlarge : ∀ n ∈ s, Real.exp V ≤ (n : ℝ)) :
        (∑ n ∈ s, (n.divisors.card : ℝ) ^ r / (n : ℝ)) ≤ Real.exp (-β * V) *
          (∏ p ∈ N.primesBelow, ∑' j : ℕ,
            ((j + 1 : ℕ) : ℝ) ^ r * ((p : ℝ) ^ (β - 1)) ^ j) := by
    …
  12. theorem OAI.Problem337.divisor_harmonic_sum_le_euler_product line 144

    Source documentation

    The unweighted finite Euler-product bound for harmonic divisor moments.

    theorem divisor_harmonic_sum_le_euler_product (r N : ℕ) (s : Finset ℕ)
        (hs : ∀ n ∈ s, n ∈ N.smoothNumbers) :
        (∑ n ∈ s, (n.divisors.card : ℝ) ^ r / (n : ℝ)) ≤
          ∏ p ∈ N.primesBelow, ∑' j : ℕ, ((j + 1 : ℕ) : ℝ) ^ r * ((p : ℝ)⁻¹) ^ j := by
    …
  13. def OAI.Problem337.divisorEulerFactor line 156

    Source documentation

    A local Euler factor, in the indexing convenient for Rankin's trick.

    def divisorEulerFactor (r p : ℕ) (β : ℝ) : ℝ :=
    …
  14. theorem OAI.Problem337.divisorEulerFactor_one_le line 159
  15. theorem OAI.Problem337.divisor_smooth_rankin_log_bound line 172

    Source documentation

    Logarithmic local-factor estimates turn the Rankin Euler product into a single exponential. This is the precise smooth-prefix bound used in the divisor-moment decomposition.

    theorem divisor_smooth_rankin_log_bound (r : ℕ) {V β C : ℝ}
        (hβ : 0 ≤ β) (hβone : β < 1) (N : ℕ) (s : Finset ℕ)
        (hs : ∀ n ∈ s, n ∈ N.smoothNumbers)
        (hlarge : ∀ n ∈ s, Real.exp V ≤ (n : ℝ))
        (hlocal : ∀ p ∈ N.primesBelow,
          Real.log (divisorEulerFactor r p β) ≤ C * (p : ℝ) ^ (β - 1)) :
        (∑ n ∈ s, (n.divisors.card : ℝ) ^ r / (n : ℝ)) ≤
          Real.exp (-β * V + C * ∑ p ∈ N.primesBelow, (p : ℝ) ^ (β - 1)) := by
    …

    Mentions: OAI.Problem337.divisorEulerFactor